Humans can acquire TB from deer

James Sunstrum, MD¹; Adenike Shoyinka, MD²; Laura E. Power, MD^2,3; Daniel Maxwell, DO⁴; Mary Grace Stobierski, DVM⁵; Kim Signs, DVM⁵; Jennifer L. Sidge, DVM, PhD⁵; Daniel J. O’Brien, DVM, PhD⁶; Suelee Robbe-Austerman, DVM, PhD⁷; Peter Davidson, PhD⁵ (View author affiliations)

View suggested citation

Article Metrics

Altmetric:

Citations:

Views:

Views equals page views plus PDF downloads

In May 2017, the Michigan Department of Health and Human Services was notified of a case of pulmonary tuberculosis caused by Mycobacterium bovis in a man aged 77 years. The patient had rheumatoid arthritis and was taking 5 mg prednisone daily; he had no history of travel to countries with endemic tuberculosis, no known exposure to persons with tuberculosis, and no history of consumption of unpasteurized milk. He resided in the northeastern Lower Peninsula of Michigan, which has a low incidence of human tuberculosis but does have an enzootic focus of M. bovis in free-ranging deer (Odocoileus virginianus). The area includes a four-county region where the majority of M. bovis–positive deer in Michigan have been found (1). Statewide surveillance for M. bovis via hunter-harvested deer head submission has been ongoing since 1995 (1); in 2017, 1.4% of deer tested from this four-county region were culture-positive for M. bovis, compared with 0.05% of deer tested elsewhere in Michigan (2). The patient had regularly hunted and field-dressed deer in the area during the past 20 years. Two earlier hunting-related human infections with M. bovis were reported in Michigan in 2002 and 2004. In each case, the patients had signs and symptoms of active disease and required medical treatment.

Whole-genome sequencing of the patient’s respiratory isolate was performed at the National Veterinary Services Laboratories in Ames, Iowa. The isolate was compared against an extensive M. bovis library, including approximately 900 wildlife and cattle isolates obtained since 1993 and human isolates from the state health department. This 2017 isolate had accumulated one single nucleotide polymorphism compared with a 2007 deer isolate (Figure), suggesting that the patient was exposed to a circulating strain of M. bovis at some point through his hunting activities and had reactivation of infection as pulmonary disease in 2017.

Whole-genome sequencing also was performed on archived specimens from two hunting-related human M. bovis infections diagnosed in 2002 (pulmonary) and 2004 (cutaneous) that were epidemiologically and genotypically linked to deer (3). The 2002 human isolate had accumulated one single nucleotide polymorphism since sharing an ancestral genotype isolated from several deer in Alpena County, Michigan, as early as 1997; the 2004 human isolate shared an identical genotype with a grossly lesioned deer harvested by the patient in Alcona County, Michigan, confirming that his infection resulted from a finger injury sustained during field-dressing. The 2002 and 2017 cases of pulmonary disease might have occurred following those patients’ inhalation of aerosols during removal of diseased viscera while field-dressing deer carcasses (4).

In Michigan, deer serve as maintenance and reservoir hosts for M. bovis, and transmission to other species has been documented (1). Since 1998, 73 infected cattle herds have been identified in Michigan (5), resulting in increased testing and restricted movement of cattle outside the four-county zone. Transmission to humans also occurs, as demonstrated by the three cases described in this report; however, the risk for transmission is understudied. Similar to Mycobacterium tuberculosis, exposure to M. bovis can lead to latent or active infection, with risk for eventual reactivation of latent disease, especially in immunocompromised hosts. To prevent exposure to M. bovis and other diseases, hunters are encouraged to use personal protective equipment while field-dressing deer. In addition, hunters in Michigan who submit deer heads* that test positive for M. bovis might be at higher risk for infection, and targeted screening for tuberculosis could be performed.^† Close collaboration between human and animal health sectors is essential for containing this zoonotic infection.

Acknowledgment

Joshua Meyerson, MD, District Health Department No. 4, Michigan.

---

¹Beaumont Health System, Dearborn, Michigan; ²Department of Epidemiology, School of Public Health, University of Michigan, Ann Arbor; ³Department of Internal Medicine, Division of Infectious Diseases, University of Michigan Medical School, Ann Arbor; ⁴MidMichigan Health, Alpena, Michigan; ⁵Michigan Department of Health and Human Services; ⁶Wildlife Disease Laboratory, Michigan Department of Natural Resources, Lansing; ⁷National Veterinary Services Laboratories, Animal and Plant Health Inspection Service, U.S. Department of Agriculture, Ames, Iowa.

All authors have completed and submitted the International Committee of Medical Journal Editors form for disclosure of potential conflicts of interest. No potential conflicts of interest were disclosed.

References

1. O’Brien DJ, Schmitt SM, Fitzgerald SD, Berry DE, Hickling GJ. Managing the wildlife reservoir of Mycobacterium bovis: the Michigan, USA, experience. Vet Microbiol 2006;112:313–23. CrossRefexternal icon PubMedexternal icon
2. Michigan Department of Health and Human Services. Michigan emerging disease issues. 2017 white-tailed deer TB testing as of March 2, 2018. Lansing, MI: Michigan Department of Health and Human Services; 2018. https://www.michigan.gov/emergingdiseases/0,4579,7-186-76711_78153-426348–,00.htmlexternal icon
3. Wilkins MJ, Meyerson J, Bartlett PC, et al. Human Mycobacterium bovis infection and bovine tuberculosis outbreak, Michigan, 1994–2007. Emerg Infect Dis 2008;14:657–60. CrossRefexternal icon PubMedexternal icon
4. Vayr F, Martin-Blondel G, Savall F, Soulat JM, Deffontaines G, Herin F. Occupational exposure to human Mycobacterium bovis infection: a systematic review. PLoS Negl Trop Dis 2018;12:e0006208. CrossRefexternal icon PubMedexternal icon
5. Michigan Department of Agriculture and Rural Development. Bovine TB identified in Alcona County herd. Lansing, MI: Michigan Department of Agriculture and Rural Development; 2018. https://www.michigan.gov/som/0,4669,7-192-26847-480387–,00.htmlexternal icon

FIGURE. Phylogenetic analysis of the most closely related Mycobacterium bovis isolates associated with human tuberculosis cases* — Michigan, 2002–2017

Abbreviation: SNP = single nucleotide polymorphism.

* The most recent common ancestor is thought to have spilled over into the local deer population from livestock at least one time during 1940–1960. All human cases are within 0–1 SNP of sharing a common ancestor with a deer isolate. Numerals denote multiple identical isolates (for example, identical M. bovis isolates from 5 deer and 1 other animal).

Suggested citation for this article: Sunstrum J, Shoyinka A, Power LE, et al. Notes from the Field: Zoonotic Mycobacterium bovis Disease in Deer Hunters — Michigan, 2002–2017. MMWR Morb Mortal Wkly Rep 2019;68:807–808. DOI: http://dx.doi.org/10.15585/mmwr.mm6837a3external icon.

MMWR and Morbidity and Mortality Weekly Report are service marks of the U.S. Department of Health and Human Services.
Use of trade names and commercial sources is for identification only and does not imply endorsement by the U.S. Department of Health and Human Services.
References to non-CDC sites on the Internet are provided as a service to MMWR readers and do not constitute or imply endorsement of these organizations or their programs by CDC or the U.S. Department of Health and Human Services. CDC is not responsible for the content of pages found at these sites. URL addresses listed in MMWR were current as of the date of publication.

All HTML versions of MMWR articles are generated from final proofs through an automated process. This conversion might result in character translation or format errors in the HTML version. Users are referred to the electronic PDF version (https://www.cdc.gov/mmwr) and/or the original MMWR paper copy for printable versions of official text, figures, and tables.

Questions or messages regarding errors in formatting should be addressed to mmwrq@cdc.gov.

from Hacker News https://ift.tt/2mcdWfA